90rxi default values
07-30-2016, 03:21 AM
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90rxi default values
Hi there.
I have a 90rxi that runs fine but is slow to start. I have done an ECU factory reset and there is one value that is different to my friends motor, also a 90RXi.
My U-accelr1: is 0.100
my mates U-accelr1: is 0.250
His starts much faster and smoother. He has never changed this value. Does anyone know which is the correct factory default.?
I have a 90rxi that runs fine but is slow to start. I have done an ECU factory reset and there is one value that is different to my friends motor, also a 90RXi.
My U-accelr1: is 0.100
my mates U-accelr1: is 0.250
His starts much faster and smoother. He has never changed this value. Does anyone know which is the correct factory default.?
07-30-2016, 04:57 AM
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I would compare what version software your ECU is running as compared to your friends first off as jetcat is always making subtle changes. The U 1 is the pump start voltage, too low and you get a low temp time out and too high you will get flames. You can adjust the U1 but go slowly. Some fuel pumps are tighter than others and do require more initial voltage. You may also want to pull the front cover off and make sure the fuel line is not pinched or has collapsed on the edge of the solenoid valve causing a restriction at that low pump voltage setting. The fuel line is a known problem and its a simple matter of a few tie wraps. As for default value .0100 and .250 are both in the acceptable range as every motor/pump is slightly different
Last edited by Jetkopter; 07-30-2016 at 04:59 AM.
07-31-2016, 02:09 AM
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Just some further info. I reset the ECU to factory , recallibrated the temp probe, set the U1 to .1 and .15 and .2 and .25 and low temp still occurs. I checked the fuel line and its not pinched. It seems to light off the goes to main fuel very quickly and then the engine spools up very fast on the electric motor. I feel the speed it turns at via the starter is very high and is causing a low temp to occur. Could it be putting out the intial flame? Also when I removed the motor there is alot of residual fuel and I feel that the fuel isn't the issue.
Any help is appreciated. Thanks again
Any help is appreciated. Thanks again
07-31-2016, 03:19 AM
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So next you need to check the main fuel solenoid for flow by removing the fuel line and do a fuel valve test . Fuel valve test is in the test functions menu. I also would like to know what is the rpm of the engine when the main fuel solenoid opens. I want to rule out that the starter is not slipping
07-31-2016, 06:18 PM
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hmm, can you spool the motor up with the gsu and tell me what rpm reading your getting? if you have a bad front board /rpm sensor the motor will go thru the pre heat and try to start but will fail because of no rpm reading. Its tough to diagnose without being in front of it !
07-31-2016, 10:42 PM
#14
You want Url 1 as low as possible to start the process. (.100 sounds about right) Then increase Url 2 3 points over where it is (.750-.995)
The excess fuel is just where the pump still runs once the initial burn has gone out, but probe still has some temp so the pump continues to run for a few seconds. When you here the 'rumble' of burning stop, pull the trim back immediately.
Its a lazy pump motor. When you get it to start ensure you run it at full power for a short time to calibrate the pump voltage and 'clear the brushes'
Url 1 varies with fuel system resistance and different pumps. But too high you still get ignition, but excess fuel in the chamber that makes Url 2 slow to kick in.
Dave
The excess fuel is just where the pump still runs once the initial burn has gone out, but probe still has some temp so the pump continues to run for a few seconds. When you here the 'rumble' of burning stop, pull the trim back immediately.
Its a lazy pump motor. When you get it to start ensure you run it at full power for a short time to calibrate the pump voltage and 'clear the brushes'
Url 1 varies with fuel system resistance and different pumps. But too high you still get ignition, but excess fuel in the chamber that makes Url 2 slow to kick in.
Dave
08-01-2016, 05:58 AM
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Hi Dave, thanks for your input.. Just confirming I set Url 1 back to .100. I have not seen Url 2 in the menu. Directly under U-accelr1 :0.100 is U-Idle which has a value of :0.60 (I don't think I can change this value?). Currently I cannot even get it to start and maintain a run.
08-01-2016, 07:45 AM
#16
Yes. With the screen showing Url 1 just press + (nothing else) and it will go to Url 2. Then you can hold change value and adjust. Will be way above U-idle
0.6-0.7 is a healthy idle voltage (usually 0.6)
Dave
0.6-0.7 is a healthy idle voltage (usually 0.6)
Dave
Last edited by Dave Wilshere; 08-01-2016 at 10:45 PM.
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